Flexible circuits are bonded with conductive adhesives and tested for proper electrical connections. The bonding area is held rigid during manufacture and use such that little or no adverse stress is placed on the bond. The applications are designed to deliberately avoid flexing the bonded region.
Structural adhesives are desired for the bond strength and tamper resistance, but are usually brittle (high glass transition temperature) and do not provide the durability demanded during usage of newer electronic devices, and further usually are not conductive.
Electrically conductive adhesive sheets have been described, for example with rigid spacer particles to maintain adhesive thickness when the adhesive is bonded. Anisotropic adhesives have been described, for example with spherical particles or regions having electrical conductivity through the thickness via patterning.